package com.ht.activiti.controller.basic;/* Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.node.ObjectNode;

import javax.annotation.Resource;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;

import org.activiti.bpmn.model.BpmnModel;
import org.activiti.editor.constants.ModelDataJsonConstants;
import org.activiti.engine.ActivitiException;
import org.activiti.engine.ProcessEngine;
import org.activiti.engine.RepositoryService;
import org.activiti.engine.repository.Model;
import org.activiti.image.ProcessDiagramGenerator;
import org.apache.batik.transcoder.TranscoderInput;
import org.apache.batik.transcoder.TranscoderOutput;
import org.apache.batik.transcoder.image.PNGTranscoder;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.web.bind.annotation.*;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;

/**
 * @author henry
 */
@RestController
@RequestMapping("service")
public class ModelSaveRestResource implements ModelDataJsonConstants {

    protected static final Logger LOGGER = LoggerFactory.getLogger(ModelSaveRestResource.class);

    @Resource
    private RepositoryService repositoryService;
    @Autowired
    private ObjectMapper objectMapper;
    @Resource
    private ProcessEngine processEngine;

    /**
     * 新建模型保存
     * @param modelId 模型id
     * @param name 模型名称
     * @param description 描述
     * @param json_xml
     * @param svg_xml
     */
    @RequestMapping(value = "/model/{modelId}/save", method = RequestMethod.PUT)
    @ResponseStatus(value = HttpStatus.OK)
    public void saveModel(@PathVariable String modelId, String name, String description, String json_xml, String svg_xml) {
        try {
            Model model = repositoryService.getModel(modelId);
            ObjectNode modelJson = (ObjectNode) objectMapper.readTree(model.getMetaInfo());
            modelJson.put(MODEL_NAME, name);
            modelJson.put(MODEL_DESCRIPTION, description);
            model.setMetaInfo(modelJson.toString());
            model.setName(name);
            repositoryService.saveModel(model);
            repositoryService.addModelEditorSource(model.getId(), json_xml.getBytes("utf-8"));
            InputStream svgStream = new ByteArrayInputStream(svg_xml.getBytes("utf-8"));
            TranscoderInput input = new TranscoderInput(svgStream);
            PNGTranscoder transcoder = new PNGTranscoder();
            // Setup output
            ByteArrayOutputStream outStream = new ByteArrayOutputStream();
            TranscoderOutput output = new TranscoderOutput(outStream);
            // Do the transformation
            transcoder.transcode(input, output);
            final byte[] result = outStream.toByteArray();
            repositoryService.addModelEditorSourceExtra(model.getId(), result);
        } catch (Exception e) {
            LOGGER.error("Error saving model", e);
            throw new ActivitiException("Error saving model", e);
        }
    }

    /**
     * 显示流程图
     * @param processDefinitionId 实例id
     * @param response 响应对象
     */
    @GetMapping("/getProcessImg")
    public void getProcessImg(@RequestParam("key") String processDefinitionId, HttpServletResponse response) {
        BpmnModel bpmnModel = repositoryService.getBpmnModel(processDefinitionId);

        ProcessDiagramGenerator processDiagramGenerator = processEngine.getProcessEngineConfiguration().getProcessDiagramGenerator();
        ServletOutputStream outputStream = null;
        InputStream inputStream = null;
        try {
            inputStream = processDiagramGenerator
                    .generateDiagram(bpmnModel, "png", new ArrayList<>(), new ArrayList<>(),
                            "宋体", "微软雅黑", "黑体", null, 2.0);

            outputStream = response.getOutputStream();
            response.setContentType("image/png");
            int bytesRead;
            byte[] buffer = new byte[8192];
            while ((bytesRead = inputStream.read(buffer, 0, 8192)) != -1) {
                outputStream.write(buffer, 0, bytesRead);
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (outputStream != null){
                try {
                    outputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (inputStream != null){
                try {
                    inputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}
